Wiring device with rubber compression wire clamp



March 2, 1954 H. HUBBELL 2,671,204

WIRING DEVICE WITH RUBBER COMPRESSION WIRE CLAMP Filed March 29, 1950 2 Sheets-Sheet l H. HUBBELL March 2, 1954 WIRING DEVICE WITH RUBBER COMPRESSION WIRE CLAMP 2 Sheets-Sheet 2 Filed March 29, 1950 W Alli/ z 4. NKRK Patented Mar. 2, 1954 UNITED STATES PATENT OFFICE WIRING DEVICE WITH RUBBER COMPRESSION WIRE CLAMP 14 Claims.

This invention relates to electric receptacles and will be found of general utility in connection therewith. Such devices are commonly employed to connect various current outlets such as sockets, plug outlets, etc., to an electric power circuit which may be, for example, a house wiring system. They are frequently mounted in wall outlet boxes, or the like.

Heretofore the operation of connecting a power circuit to one or more receptacles has usually required the use of binding screws or similar securing means for each individual wire, so that the operation has taken considerable time and been difiicult to carry out in cramped places in which there i lIlSlllllClBIlt space to work.

An object of this invention is to provide an electric receptacle constructed and arranged to eliminate all binding screws and to greatly simplify and expedite the operation of connecting the receptacle to a circuit.

A further object is to provide an improved electric receptacle arranged to permit the wires or" a power circuit or the like being connected thereto merely by inserting the stripped ends of the wires into the receptacle, and then simultaneously clamping all wires in place in a single easy operation.

A further object is to provide an electric receptacle of such construction that the insertion of a wire conductor into the receptacle serves to electrically connect it to the receptacle contacts, while any efiort to withdraw the wire therefrom serves to increase the clamping effect and prevent such withdrawal until the wire is intentionally released.

A further object is to provide an electric receptacle arranged to guide the stripped ends of the circuit wires into the correct positions in the receptacle as they are inserted therein.

With the foregoing and other objects in view, I have devised the construction illustrated in the accompanying drawings forming a part of this specification. It is, however, to be understood the invention is not limited to the specific details of construction and arrangement shown, but may embody various changes and modifications within the scope of the invention.

In these drawings:

Fig. 1 is a front elevation of an electric receptacle illustrating one embodiment of the invention;

Fig. 2 is a side elevation, partly in section, of the receptacle shown in Fig. 1;

Fig. 3 is a rear elevation of the receptacle shown in Figs. 1 and 2;

Fig. 4 is a transverse section on the line 4-4 of Fig. 1;

Fig. 5 is a similar view of a modified construction;

Fig. 6 is a perspective view of a detail;

Fig. '7 is a partial section on the line 11 of Fig. 5, and

Figs. 8 and 9 are top and side views respectively, of one form of contact assembly, as employed in the illustrated embodiments of the invention.

The particular embodiment of the invention which has been chosen for illustration is shown in connection with an outlet receptacle for use with plug type connectors. As illustrated, it includes a body or housing H of any suitable insulating material having a pair of openings or slots 12 and 13 adjacent opposite ends to receive the blades of plug type electric connectors or attachment plug caps. Blade receiving electric contacts is are provided at the rear of the T-shaped blade receiving slots or openings I2 and i3 and include spring ears l5 and [5a to grip the blades. The contacts l4 adjacent one side edge of the casin and at opposite ends thereof are mounted on base plates I la mechanically and electrically connected by a contact plate It extending longitudinally along the adjacent side of the casing. Each plate It and its associated contacts I l form an integral assembly unit which can be easily located in place in the body or housing I I. When in place in the housing the contact plates converge, as shown in Figs. 4 and 5, and are supported on inclined converging shoulders or walls I! extending longitudinally along each inner side wall E8 of the housing H and forming part of the side walls of chamber Hb in this housing. The inner edge 19 of each contact plate [5 is shown as having a series of notches or recesses 2| for engagement with the main circuit wires or the like, to be connected to the receptacle, as hereinafter described. The edges l9 project beyond the inner edges of the supporting walls ll. The housing H is formed with inner insulating partitions 280. which separate the contacts M from the contact plates 56 and from each other, connecting straps 28 extending across the ends of the partitions. In this way the different parts of the contact assembly are isolated behind insulating walls to reduce the possibility of short circuits. 7

The interior of the housing between the par titions Ha is substantially filled by a block 22 of relatively soft resilient insulating material having extensions 23 at each end extending past the partitions Ila. and enclosing the blade re- 3 ceiving contacts l4 and retaining them in their proper compartments in the body I i, which compartments open through the back of the body member for insertion and removal of the contacts l4 and block 22. The block 22 may be rubher or other suitable yieldable resilient material, either natural or synthetic. As shown in Figs. 4 and 5, the insulating block 22 has converging longitudinally extending side walls 24 which engage the contact plates 45 and retain them in place. Each side of the block 22 is provided with a series of openings 25 through which the stripped ends of main circuit conductors 27 forming, for example, a house wiring circuit, can be inserted for connection to the contact plates 16. As shown in Figs. 3 and l, each opening 25 has a countersink 26 to accommodate the end of the insulating cover on a conductor inserted into the opening. Mechanism is provided for distorting the resilient block 22 to press the conductors 27 into contact with the recessed edges i9 of the contact plates it. As shown in Fig. 4, a compressor plate 28 is molded in the block 22 so that it is floating in the rubber or other resilient material of the block, and it is threaded at 28a to the end of a clamping bolt 29 extending through aligned openings 3i and 32 respectively in the housing H and the block 22. If desired, the compressor plate 28 can engage the outer face of the block 22, instead of bein embedded therein. In Fig. 5, a compressor plate 33 corresponding to plate 28 extends across the openings 25 in the block 22 and has aligned openings 33a through which the conductor wires 2'5 may be inserted.

In the embodiment illustrated in Figs. and 7, a wire guide 34 is mounted in a slot 32a in the block 22 opposite each opening for guiding the end of a conductor wire as it is inserted into the receptacle and for pressing such wire into clamping engagement with the adjacent edge of the retaining contact plate 16. Each guide 3 has a groove 35 for accommodating and guiding the associated wire 2?, the end of the groove into which the wire first engages having a beveled or laterally flared edge 36 (see Figs. 5 and 6) for guiding the entering movement of the wire.

As shown in Figs. 1, 2 and 3, a U-shaped strap 3-! having a perforated ear 38 at each end is pro vided for mounting the receptacle in any suitable place, such, for example, as in a wall outlet box (not shown). The strap is connected to the receptacle by the clamping bolt or screw 29 which extends rotatably through the strap and is loosely riveted or otherwise secured to it, as shown at 29a. This screw secures the various parts of the receptacle together and its head 290 is exposed for operation of the screw at the front side of the receptacle by a screw driver, for example, in the slot 291).

In use, the clamping plate 28 or 33 is first positioned by adjustment of the clamping bolt or screw 29 so that the resilient block 22 is undistorted, that is, not subjected to any compressing or distorting force. Under this condition the stripped ends of conductors, such as the wires 21 forming the house circuit, can be easily inserted into the receptacle through the openings 25 until the ends of the wires extend past the edges of the contact plates It, as shown in Figs. 4 and 5. Thereupon, adjusting the clamping bolt 29 to distort or compress the resilient block 22 causes the material to press against the conductorwires '21 and hold or clamp them against the edges of the contact plates IE. This pressure of the wires on the plates not only assures a good electrical contact, but also prevents their withdrawal by any pulling or tension which may be applied to them. The edges of the plates may cut or bite into the wire to a certain extent to increase the grip. Any withdrawal movement of the wires which frictionally engage the edges of the contact plates causes the latter to cam against the surface of the wires and bite into them with a retaining force proportional to the pull on the wires and thereby lock them in place.

It will be understood that a conductor wire forming one side of a house circuit, for example, will be inserted through an opening 25 leading to one contact plate [5, while a wire forming the other side will be connected to the other contact plate. By providing, as illustrated, multiple openings 25 so that multiple wires can be connected to each plate IS, the receptacle can be connected into a circuit at any point, and branch circuits connected if desired.

Although I have described in detail certain specific embodiments of the invention, it will be apparent that the invention can be variously modified and adapted within the scope of the appended claims.

Having thus set forth the nature of my invention, I claim:

1. An electric receptacle comprising a housing of insulating material formed to permit an electric conductor to be inserted therein, electrical contacts in said housing, a contact plate electrically connected to said contacts and supported on one side by said housing, a resilient insulating member adjacent said contact plate on the opposite side thereof and having openings formed to permit said conductor to be inserted into said housing between the member and plate past an edge thereof at an inclined angle to the plane of the plate, and means for distorting said resilient insulating member to press the side of said conductor against the edge of said plate and at an angle to said plate,

whereby said conductor is electrically connected to said contacts and is retained against withdrawal from the outlet receptacle by the camming action of said plate which causes the edge thereof to clamp the conductor in place.

2. An electric receptacle comprising a housing of insulating material formed to permit an electric wire conductor to be inserted therein, electrical contacts in said housing, a contact plate electrically connected to said contacts and supported on one side by said housing, a resilient insulating member adjacent said contact plate on the opposite side thereof having openings formed to permit said conductor to be inserted into said housing between the member and plate past an edge thereof at an inclined angle to the plane of the plate, and means for distorting said resilient insulating member to press the side of said conductor against the edge of said plate and at an angle to said plate, whereby said concluctor is electrically connected to said contacts and is retained against withdrawal from the outlet receptacle by the camming action of said plate which causes the edge thereof to clamp the conductor in place, and means for guiding said conductor wire inserted into said housing into position between said resilient insulating member and the edge of said contact plate at an angle to the plane of said plate.

3. An electric receptacle comprising a'housing formed to permit an electric wire conductor to be inserted therein, electrical contacts in said housing, a contact plate electrically connected to said contacts, a resilient insulating member adjacent said contact plate having openings formed to permit said conductor to be inserted into said housing between the member and plate at an angle to the plane of the plate, and means for distorting said insulating member to press the side of said conductor against the edge of said plate and at an angle to said plate, whereby said conductor is electrically connected to said contacts and is retained against withdrawal from the outlet receptacle by the camming action of said plate which causes the edge thereof to clamp the conductor in place, and means for guiding said conductor wire inserted into said housing into position between said insulating member and the edge of said contact plate at an angle to the plane of said plate, including a wire guiding member mounted on said insulating member at the side of said openings opposite said contact plate.

4. An electric receptacle comprising a housing formed to permit an electric conductor wire to be inserted therein, electrical contacts in said housing, a, contact plate electrically connected to said contacts, a resilient insulating member adjacent said contact plate having openings formed to permit said conductor to be inserted into said housing between the member and plate at an angle to the plane of the plate, and means for distorting said insulating member to press the side of said conductor against the edge of said plate and at an "angle to said plate, whereby said conductor is electrically connected to said contacts and is retained against withdrawal from the outlet receptacle by the camming action of said plate which causes the edge thereof to clamp the conductor in place, and means for guiding said conductor wire inserted into said housing into position between said insulating member and the edge of said contact plate at an angle to the plane of said plate including a wire guiding member mounted in a plate receiving slot in said insulating member on the side of said opening opposite to said contact plate.

5. A duplex electric receptacle comprising a housing having adjacent each end a pair of contacts adapted to engage the blades of separate plug connectors inserted through the front of the housing, a contact plate extending longitudinally along each opposite side of the housing and electrically connected to that one of each of said pairs of contacts adjacent thereto, the planes of said contact plates converging inwardly, a resilient block of insulating material positioned between the converging inner ends of said plates and having a conductor receiving opening extending through the block, whereby a conductor inserted through said opening will extend past the inner edge of the adjacent plate and be pressed into contact therewith by the resilient insulating material.

6. A duplex electric receptacle comprising a housing having adjacent each end a pain of contacts adapted to engage the blades of sepa rate plug connectors inserted through the front of the housing, a contact plate extending longitudinally along each opposite side of the housing and electrically connected to that one of each of said pairs of contacts adjacent thereto, the planes of said contact plates converging inwardly, a member of resilient insulating material positioned between the converging inner ends of said plates and having conductor receiving openings extending through. opposite sides of the material from the rear face of the housing to points adjacent the inner edges of said plates, whereby a conductor inserted through one of said openings from the back of the housing will extend past the inner edge of the adjacent plate, and means for distorting said insulating material to press said conductor into contact with said plate edge to electrically connect said conductor or to said contacts and secure said conductor against withdrawal from the receptacle.

7. A duplex electric receptacle comprising a a housing having adjacent each end a pair of contacts adapted to engage the blades of separate plug connectors inserted through the front of the housing, a contact plate extending longitudinally along each opposite side of the housing and electrically connected to that one of each of said pairs of contacts adjacent thereto, the planes of said contact plates converging inwardly, a member of resilient insulating material positioned between the converging inner ends of said plates and having conductor receiving openings extending through opposite sides of the material from the rear face of the housing to points adjacent the inner edges of said plates, whereby a conductor inserted through one of said openings from the back of the housing will extend past the inner edge of the adjacent plate, and means for distorting said insulating material to press said conductor into contact with said plate edge to electrically connect said conductor to said contacts and secure said conductor against withdrawal from the receptacle, including a compression plate engaging said insulating material, and a clamping bolt extending throughthe housing and said block and threaded to said compression plate whereby to compress saidblock and press the conductor against the contact plate.

8. An electric receptacle comprising an insulating body member provided with a chamber, an electrical contact in said chamber including an inclined plate supported at one side thereof by a side of the chamber, a member of resilient insulating material in the chamber at the opposite side of said plate provided with an opening for insertion of a conductor wire between the resilient member and said plate, a compression plate mounted in said resilient member, and a screw threaded into said compression plate and provided with means at one side of the body for operation of the screw to force the compression plate against the resilient material and spread this material to clamp the wire against the first plate.

9. An electrical device of the character described, comprising a body member of insulating material provided with a chamber, a stationary contact in the body, a contact plate in the chamber connected with said contact and provided with a free edge, said plate being supported on one side by a wall of the chamber, a member of resilient insulating material in said chamber at the opposite side of the plate and provided with means for guiding an inserted conductor Wire to a position between the free edge of the plate and the resilient member and inclined to the plate, and means for compressing the resilient member to cause it to press the Wire against the edge of the plate to be gripped and held against withdrawal by said edge and to form electrical contact with the plate.

10. An electrical receptacle comprising an insulating body member provided with a chamber, spaced receptacle contacts in the body, a conductor means connecting said contacts including a contact plate mounted in an inclined position in said chamber and having an inner free edge, said plate being supported on one side by a wall of the chamber, a block of resilient insulating material in the chamber at the opposite side of the plate provided with means for guiding an inserted conductor wire past said free edge between the plate and said block, and means to compress the block longitudinally to cause itto tend to spread laterally to press the wire against said free edge to be gripped and held thereby against withdrawal and form electrical contact with the plate.

11. An electrical receptacle comprising an insulating body member provided with a chamber, spaced receptacle contacts in the body, a conductor means connecting said contacts including a contact plate in the chamber having a free inner edge, said chamber being provided with an inclined wall supporting the plate in an inclined position, a block of resilient insulating material in the chamber at one side of the plate provided with means to guide an inserted conductor wire past said free edge to a position between the plate and said block, and means to compress the block longitudinally to cause it to expand laterally and press the wire against said free edge to grip and hold the wire against withdrawal and form electrical contact with the plate.

12. An electrical receptacle comprising an insulating body member provided with a chamber, spaced receptacle contacts in the body, a conductor means connecting said contacts including a contact plate mounted in the chamber and provided with a wire gripping means, said plate being supported on one side by a wall of the chamber, a block of resilient insulating material mounted in the chamber at the opposite side of said plate and provided with means for guiding an inserted conductor wire to a position between said resilient member and the gripping means on the plate, and means to compress the block longitudinally to cause it to expand laterally and clamp the wire against the gripping means to secure it against withdrawal and form electrical contact with the plate.

13. An electrical receptacle comprising a body member of insulating material provided with a chamber, a receptacle contact in the body, means for connecting a lead wire with said contact comprising a contact plate mounted in the chamber in an inclined position and having an inner free edge, said plate being supported on one side by a wall of the chamber, a resilient insulating member mounted in the chamber on the opposite side of said plate and provided with means to guide the lead wire to a position between said resilient member and said free edge, and means for compressing the resilient member to cause it to press the wire against the edge of the plate to be gripped and held thereby against withdrawal and form electrical contact with the plate.

14. An electrical receptacle comprising an insulating body member provided with a chamber opening through its rear wall, spaced receptacle contacts in the body, conductor means connecting said contacts including a contact plate mounted in said chamber in an inclined position and provided with an inner free edge, said plate being supported on one side by a wall of the chamber, a block of resilient insulating material in the chamber at the opposite side of said plate provided with means for guiding an inserted conductor wire to a position between the block and plate and past said free edge, a compression plate adjacent the rear side of the block, and a screw extending from the front of said body to the compression plate and connected therewith to shift it forwardly and compress the block longitudinally to cause it to spread laterally and press the wire against said free edge to cause it to be gripped and held thereby against withdrawal and form electrical connection with the contact plate.

' HARVEY HUBB'ELL.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,817,441 Madigan Aug. 4, 1931 1,982,077 Spencer Nov. 27, 1934 2,075,674 Te Pas Mar. 30, 1937 2,228,334 Abbott Jan. 14, 19 11 2,262,712 Shenton Nov. 11, 1941 2,476,227 Sellers July 12, 1949 2,500,181 Hubbell Mar. 14, 1950 

